Laryngotracheal Amyloidosis: Amyloid Airway Center 23-Year Experience

OBJECTIVES

Localized laryngotracheal amyloidosis (LA) is a rare disease that can impact phonation and respiration. Treatment options include observation, surgery, and radiation therapy (RT). Given the rare incidence of LA, evidence regarding optimal management and long-term outcomes is limited.

STUDY DESIGN

Retrospective cross-sectional analysis.

METHODS

All patients with LA presenting to an international amyloid center from 1999 to 2022 were analyzed. Patients were categorized by treatment modality: surgery, RT, or observation. Patient and disease factors including demographics, clinical presentation, and progression with need for additional treatment were evaluated.

RESULTS

Seventy-one patients (27M:44F) with LA were treated with surgery (n = 40), RT (n = 11), and observation (n = 20). Gender distribution, age at diagnosis, and systemic workup did not differ significantly between treatment cohorts. A correlation was identified between LA location and treatment modality, with higher rate of subglottic/tracheal amyloid in RT patients vs. surgery and observation patients [(90% and 52% respectively), p < 0.005]. Surgery patients had a median of two surgeries for disease management (range: 1-32) and RT patients had median five surgeries prior to RT (range: 0-17). Six patients required tracheotomy: 3/40 surgery, 3/11 RT and 0/20 in observation cohort. Surgery and RT patients had a longer duration of follow-up (mean 6.7 and 11.7 years) compared with the observation cohort (5.7 years).

CONCLUSION

Laryngotracheal amyloidosis is a rare disease with variable presentation. Selective surgery of involved subsites is the primary treatment, though multiple surgeries may be needed to optimize function. Observation is appropriate for those with minimal symptoms. For recalcitrant disease, and particularly subglottic/tracheal amyloid, radiotherapy can be beneficial.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1606-1613, 2024.

Low-Dose Whole Brain Radiation Therapy for Alzheimer's Dementia: Results From a Pilot Trial in Humans

PURPOSE

We report neurocognitive, imaging, ophthalmologic, and safety outcomes following low-dose whole brain radiation therapy (LD-WBRT) for patients with early Alzheimer dementia (eAD) treated in a pilot trial.

METHODS AND MATERIALS

Trial-enrolled patients were at least 55 years of age, had eAD meeting NINCDS-ADRDA (National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association) Alzheimer's Criteria with confirmatory fluorodeoxyglucose and florbetapir positron emission tomography findings; had the capacity to complete neurocognitive function, psychological function, and quality-of-life assessments; had a Rosen modified Hachinski score ≤4; and had estimated survival >12 months.

RESULTS

Five patients were treated with LD-WBRT (2 Gy × 5 over 1 week; 3 female; mean age, 73.2 years [range, 69-77]). Four of 5 patients had improved (n = 3) or stable (n = 1) Mini-Mental State Examination (second edition) T-scores at 1 year. The posttreatment scores of all 3 patients who improved increased to the average range. There were additional findings of stability of naming and other cognitive skills as well as stability to possible improvement in imaging findings. No safety issues were encountered. The only side effect was temporary epilation with satisfactory hair regrowth.

CONCLUSIONS

Our results from 5 patients with eAD treated with LD-WBRT (10 Gy in 5 fractions) demonstrate a positive safety profile and provide preliminary, hypothesis-generating data to suggest that this treatment stabilizes or improves cognition. These findings will require further evaluation in larger, definitive, randomized trials.

Radiation as a Tool against Neurodegeneration-A Potential Treatment for Amyloidosis in the Central Nervous System

Radiotherapy (RT) is a relatively safe and established treatment for cancer, where the goal is to kill tumoral cells with the lowest toxicity to healthy tissues. Using it for disorders involving cell loss is counterintuitive. However, ionizing radiation has a hormetic nature: it can have deleterious or beneficial effects depending on how it is applied. Current evidence indicates that radiation could be a promising treatment for neurodegenerative disorders involving protein misfolding and amyloidogenesis, such as Alzheimer's or Parkinson's diseases. Low-dose RT can trigger antioxidant, anti-inflammatory and tissue regeneration responses. RT has been used to treat peripheral amyloidosis, which is very similar to other neurodegenerative disorders from a molecular perspective. Ionizing radiation prevents amyloid formation and other hallmarks in cell cultures, animal models and pilot clinical trials. Although some hypotheses have been formulated, the mechanism of action of RT on systemic amyloid deposits is still unclear, and uncertainty remains regarding its impact in the central nervous system. However, new RT modalities such as low-dose RT, FLASH, proton therapy or nanoparticle-enhanced RT could increase biological effects while reducing toxicity. Current evidence indicates that the potential of RT to treat neurodegeneration should be further explored.

Localized Amyloidosis of the Nasal Mucosa: A Case Report and Review of the Literature

Amyloidosis is a disorder of protein folding in which various proteins automatically aggregate into a highly abnormal fibrillar conformation. Amyloidosis is classified into systemic and localized forms depending on whether the abnormal proteins deposited in several different organs or only a single organ. In localized amyloidosis of the head and neck regions, laryngeal amyloidosis is common; however, localized amyloidosis of the nose is extremely rare. We herein report a case of localized amyloidosis of the nose and review the relevant literature on localized sinonasal amyloidosis. A 41-year-old man presented with a history of severe nasal obstruction, which had persisted for two decades. Nasal endoscopy and imaging studies showed extensive thickening of the bilateral nasal mucosa and diffuse submucosal deposition of calcification. After histopathological and systemic examinations, he was diagnosed with localized amyloidosis of the nasal mucosa. Septoplasty and bilateral inferior turbinoplasty, which consisted of mucosal resection using an ultrasonic bone curette, was performed and his symptoms markedly improved. Localized sinonasal amyloidosis has a good prognosis and surgical resection should be selected as a first-line treatment; however, clinicians should recognize the high probability of recurrence.

Treatment by low-dose brain radiation therapy improves memory performances without changes of the amyloid load in the TgF344-AD rat model

Alzheimer's disease (AD) is a neurodegenerative condition affecting memory performance. This pathology is characterized by intracerebral amyloid plaques and tau tangles coupled with neuroinflammation. During the last century, numerous therapeutic trials unfortunately failed highlighting the need to find new therapeutic approaches. Low-dose brain radiotherapy (LD-RT) showed efficacy to reduce amyloid load and inflammation in patients with peripheral diseases. In this study, the therapeutic potential of 2 LD-RT schedules was tested on the TgF344-AD rat model of AD. Fifteen-month-old rats were irradiated with 5 fractions of 2 Gy delivered either daily or weekly. The daily treatment induced an improvement of memory performance in the Y-maze. In contrast, the weekly treatment increased the microglial reactivity in the hippocampus. A lack of effect of both regimens on amyloid pathology was unexpectedly observed. The positive effect on cognition encourages to further evaluate the LD-RT therapeutic potential and highlights the impact of the design choice of the LD-RT regimen.

Low-Dose Radiation Therapy: A New Treatment Strategy for Alzheimer's Disease?

Alzheimer's disease (AD) is a neurodegenerative disease characterized by extracellular amyloid-β (Aβ) peptide aggregates, forming amyloid plaques, and intracellular deposits of phosphorylated tau. Neuroinflammation is now considered as the third hallmark of AD. The majority of clinical trials tested pharmacological strategies targeting amyloid, tau, and neuroinflammation, with disappointing results overall. In parallel, innovative strategies exploring other pathways and approaches are being tested. In this article, we focus on the rationale and preliminary preclinical evidence for a novel application to AD of a widely used therapeutic strategy for oncological and benign conditions: low-dose radiation therapy (LD-RT). LD-RT has shown to be effective against systemic amyloid deposits, as well as against chronic inflammatory diseases, and could thus be able to modulate amyloid load and neuroinflammation in AD. The anti-amyloid effect could be possibly mediated by the LD-RT action on the β-sheet structure of amyloid fibrils, by breaking H-bonds, and depolymerize glucoaminoglycans which are highly radiation-sensitive molecules associated with amyloid fibrils. The anti-inflammatory effect could be linked to the decrease of leukocytes-endothelial cells interactions and to the stimulation of the release of anti-inflammatory molecules. One preclinical study has observed a dramatic reduction of amyloid plaques 4 weeks post-RT, more important with fractionated protocols at low doses than hypofractionated single dose treatments, associated with modulation of inflammatory and anti-inflammatory cytokines and cognitive improvement. Ongoing Phase I clinical trials will test the ability of LD-RT to hold these promises.

One Hundred Cases of Localized Laryngeal Amyloidosis - Evidence for Future Management

OBJECTIVE/HYPOTHESIS

To update the current understanding of localized laryngeal amyloidosis by analyzing the NHS National Amyloidosis Database and to further clarify the important ongoing management issues.

STUDY DESIGN

Retrospective review, case series.

METHODS

Patients with laryngeal amyloid were identified from the database of the NHS National Amyloidosis Center, UCL, Royal Free Hospital, London between 2000 and 2017. Patient demographics and disease profile were collated, including the exact location of amyloid deposit, treatments if any, and progression of disease.

RESULTS

One hundred and three patients with localized laryngeal amyloid where identified from the database, with a mean age of 54 at diagnosis and female to male ratio of 54:49. Three patients were excluded from further analysis due to limited database information. The majority of amyloid was found in either the supraglottis (44) or glottis (53) but all the laryngeal subsites were involved. One-third of the patients (34) had amyloid in more than one laryngeal subsite. No patients were found to progress to systemic amyloid, but many progressed locally to other subsites or further down the LTB tree (29%). Three patients were successfully treated with radiotherapy after other modalities had failed.

CONCLUSIONS

This is the largest case series reported to date of localized laryngeal amyloidosis. It highlights the high incidence of multifocal disease and the significant proportion of patients who progressed, not to systemic amyloidosis but to more extensive localized amyloid. We recommend that in all cases of laryngeal amyloid, patients should undergo a thorough assessment of the upper and lower airways and have ongoing surveillance for at least 15 years.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E1912-E1917, 2021.

Long-term Follow-up After Radiation Therapy for Laryngeal Amyloidosis

OBJECTIVES

Laryngeal amyloidosis (LA) is a rare disease characterized by extracellular protein deposition within the larynx. Treatment is difficult due to the frequently submucosal and multifocal nature of disease. The mainstay of treatment is surgical resection; however, recurrence rates are high. Recently, use of radiotherapy (RT), either alone or postoperatively, for LA has been adapted from the management of extramedullary plasmacytoma and has been shown to provide local disease control. Here, we describe the experience with adjuvant RT for LA at our center.

STUDY DESIGN

Retrospective case series.

METHODS

Retrospective study of patients with amyloidosis of the larynx, with or without other disease sites, seen at a tertiary academic center between 2011 and 2019. Outcomes included disease characteristics, recurrence rates, treatment modalities, and pre- and posttreatment voice handicap index (VHI)-10.

RESULTS

Ten patients met eligibility criteria. Mean follow-up time for all patients was 62.0 ± 41.0 months; mean follow-up time after last treatment was 51 ± 55 months. All but one patient underwent surgical resection of disease. Seven patients underwent subsequent RT. Of these seven, six underwent RT at our institution; five received a dose of 45 Gray (Gy); and one received a dose of 20 Gy. All seven completed RT without toxicity-related interruption. Patients undergoing RT underwent 2.1 ± 1.3 surgical procedures prior to RT; no patients required surgery after RT. Mean pretreatment VHI-10 was 22.9 ± 8.1; mean posttreatment VHI-10 was 12.9 ± 13.3.

CONCLUSION

RT after surgery for LA can provide good local control without unacceptable toxicity and may decrease the need for further surgery.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1810-1815, 2021.

Clinical Profile of Patients with Head and Neck Amyloidosis: A Single-Institution Retrospective Chart Review

Introduction  Isolated amyloidosis involving the head and neck is a rare entity. The pathophysiology of the localized disease appears to be distinct from that of the systemic counterpart. Systemic progression of the localized disease is unusual, and the prognosis of the localized form is excellent.

Objective  To describe the demographic and clinicopathological characteristics of patients presenting with localized head and neck subsite amyloidosis.

Methods  A retrospective chart review of the patients with head and neck amyloidosis identified by the electronic search of the electronic database of the Departments of Pathology and Otorhinolaryngology was performed. The various demographic and clinical data were tabulated.

Results  In total, seven patients (four females, three males) with localized head and neck amyloidosis (three supraglottic, three lingual and one sinonasal) were identified. Six patients had AL-amyloid deposits, and one patient had AA-amyloid deposits. Supraglottic involvement and that of the base of the tongue were treated surgically using CO2 laser, and these patients were disease-free at the last follow-up. The patient with sinonasal amyloidosis experienced symptom recurrence after six months of the functional endoscopic sinus surgery. All of the patients were screened for systemic amyloidosis with abdominal fat pad biopsy, and were found to be free of systemic spread.

Conclusion  Isolated head and neck amyloidosis, as opposed to systemic amyloidosis, has an excellent prognosis in terms of survival. Therefore, systemic amyloidosis should be excluded in all cases. The treatment of choice remains surgical excision; however, watchful waiting may be a suitable strategy for mild symptoms or for cases in which the disease was discovered incidentally.

Laryngeal amyloidosis: diagnosis, pathophysiology and management

Background:

Laryngeal amyloidosis represents approximately 1 per cent of all benign laryngeal lesions, and can cause variable symptoms depending on anatomical location and size. Treatment ranges from observation through to endoscopic microsurgery, laser excision and laryngectomy.

Objectives:

To highlight the diversity of presentations, increase awareness of paediatric amyloidosis and update the reader on current management.

Case series:

Five cases are illustrated. Four adult patients were female, and the one child, the second youngest in the literature, was male. Amyloid deposits were identified in all laryngeal areas, including the supraglottis, glottis and subglottis. Treatment consisted of balloon dilatation, endoscopic excision, laser cruciate incision, and resection with carbon dioxide laser, a microdebrider and coblation wands.

Conclusion:

Laryngeal amyloidosis remains a rare and clinically challenging condition. Diagnosis should be considered for unusual appearing submucosal laryngeal lesions. Treatment of this disease needs to be evaluated on a case-by-case basis and managed within an appropriate multidisciplinary team.

Long-term follow-up after surgery in localized laryngeal amyloidosis

To study effectiveness of surgery and watchful waiting in localized laryngeal amyloidosis, retrospective case series. This retrospective study comprises all consecutive patients with localized laryngeal amyloidosis surgically treated in a tertiary hospital between 1994 and February 2016. Recurrence rate, revision surgery, progression to systemic amyloidosis, and changes in voice were monitored yearly. Eighteen patients were included. Seven women and eleven men had a median age 50 years (range 21-77 years) and median follow-up 6.4 years (2.4-17 years). Amyloid was located in subglottis (5), glottis (8), false vocal folds (8) and other supraglottic areas (5), in more than one laryngeal region (13) and bilaterally (12). Cold steel excision was used at the glottis; CO2 laser excision, sometimes assisted by microdebrider, at other laryngeal areas. Eleven patients needed revision surgery, ten within the first 4 years after surgical treatment. One patient needed his first revision surgery after 11 years. Five patients needed a second revision within 6 years after initial diagnosis. Two patients needed a third revision. Indications for first revision surgery were progression (8) with dysphonia (7), dyspnea (2), dysphagia (1), exclusion of malignancy (1), and aphonia (1). No patient developed systemic amyloidosis during follow-up. Although local progression of amyloid necessitates revision surgery once or twice in the first 4-6 years, progression slows down thereafter. Late progression, however, remains possible.

Tracheobronchial amyloidosis managed with multimodality therapies

Amyloidosis is a systemic disease involving abnormal extracellular deposition of amyloid and autologous fibrillar protein material in β-pleated sheets. Accumulation of this abnormal protein leads to organ dysfunction, although respiratory tract involvement is rare. We present two cases of tracheobronchial amyloidosis successfully treated with surgery and radiation.

Management of Upper Aerodigestive Tract Amyloidosis

Objectives:

The aim of this study was to discuss the treatment options for upper aerodigestive tract amyloidosis.

Methods:

Four patients with histologically confirmed amyloidosis were included in the study. All patients underwent surgical treatment. Three patients had laryngeal amyloidosis, and 1 patient had tonsillar amyloidosis.

Results:

Two of the cases of laryngeal amyloidosis were successfully treated with a combination of surgery and radiation therapy. One case of laryngeal amyloidosis was treated with surgery alone. The tonsillar amyloidosis was removed by tonsillectomy. None of the cases showed systemic involvement. Long-term follow-up of the patients showed no recurrence or evidence of systemic disease.

Conclusions:

Surgical resection is the primary treatment for patients with upper aerodigestive tract amyloidosis. Radiation therapy is especially effective in cases of recurrent amyloidosis with submucosal involvement. Pedunculated polypoid lesions may be treated with surgery alone, and in cases of recurrence, irradiation following the surgical removal should be considered. Tonsillectomy is usually sufficient for treating tonsillar amyloidosis.

How to deal with laryngeal amyloidosis? Experience based on 16 cases

INTRODUCTION

Amyloidosis is characterized by the deposition of amorphous fibrillar protein (amyloid) in the intercellular or intracellular space. Localized amyloidosis is rare in the head and neck area. In Polish literature of the last decade it has been the subject of case studies.

AIM

The goal of the study was to carry out a retrospective analysis of patients treated for amyloidosis in the Department of Otolaryngology and Head and Neck Surgery of the Poznań University of Medical Sciences in the period from 2000 to 2009. Based on the collected clinical material, the authors made an attempt to determine the most frequent anatomical location of amyloid deposits and the most frequently affected organs, the type and duration of symptoms, the therapeutic approach, further diagnostic measures taken and the final outcome of the treatment. The next goal was to assess the number of microlaryngoscopies performed in patients with amyloidosis affecting the larynx as compared to the overall number of such procedures.

MATERIAL

The detailed analysis included 16 patients with laryngeal amyloidosis.

RESULTS

Amyloidosis of the larynx was found in only 0.52% of patients undergoing microlaryngoscopies in the period from 2000 to 2009. In the vast majority of patients (11 of 16), there was no suspicion of amyloidosis in the initial diagnosis. Only the histopathological assessment definitely confirmed the nature of pathological changes in the larynx. Glottis was the most common location of amyloid deposits in the study group. In all cases, additional studies and long-term monitoring of the postoperative course excluded generalized amyloidosis.

CONCLUSIONS

Laryngeal amyloidosis is very rare, however it should be considered in the differential diagnosis in patients with laryngeal dysfunction. Surgery remains the treatment of choice in most patients, although the attempts of radiotherapy are undertaken. Preserving the normal function of the organ remains the priority.

How to manage primary amyloidosis

Immunoglobulin light chain amyloidosis is a protein deposition disorder where the precursor protein represents a monoclonal immunoglobulin light or heavy chain. Deposition in viscera results in restrictive cardiomyopathy, nephrotic range proteinuria, demyelinating peripheral neuropathy, hepatomegaly and malabsorption syndrome. Diagnosis requires biopsy with Congo red staining. Invasive biopsies are not required generally. It is essential that after a histologic diagnosis is obtained, the tissue is validated to have an immunoglobulin light chain composition so patients are spared unnecessary chemotherapy. The disease prognosis and patient monitoring are linked to serialized measurement of cardiac biomarkers and immunoglobulin-free light chains. Most patients require cytotoxic chemotherapy. For some patients, this therapy involves stem cell collection and myeloablative chemotherapy; for others, chemotherapy includes an alkylator and a corticosteroid; and for some, it involves addition of a novel agent in the form of an immunomodulatory drug or a proteasome inhibitor. Delays in diagnosis continue to be an obstacle to initiating effective therapy. Early mortality rates remain high. Effective chemotherapy can result in reversal of organ dysfunction and recovery. Reductions in light chain production translate to improved survival.